So how do users like them? Kevin Carr, director of IT for the County of Denton, was quickly running out of network capacity as he moved 150 physical servers to VMware on a Cisco-based network. He added in the Cisco Nexus 1000v to ease the pain.

"We have a lot more capacity than we need so we can say yes to every server request and deliver VMs super fast over the network," said Carr.

The City and County of San Francisco also added Cisco Nexus 1000V switches along with Cisco Unified Compute System (UCS) blades to create its converged network. This platform is being used to move from a distributed infrastructure consisting of 40 data centers and server rooms spread all around the city.

The strategy is to virtualize 335 Windows servers onto 25 UCS blades and Nexus 1000v switches on a VMware with EMC Storage. He has set a two-year horizon to arrive at a fully virtual data center.

"We are using VMware, Cisco UCS/Nexus 1000V and an EMC SAN to facilitate the private cloud," said Jonathan Walton, Deputy CIO, for both the City and County of San Francisco. "We are moving towards the provision of a private cloud to multiple agencies."

As well as the Cisco Nexus 1000V, he also looked at virtual networking tools from Juniper Networks. He went with Cisco as it better forwarded the centralization of IT procurement and management in a fully virtualized arena.

"Cisco and VMware are complementary, so even though we now have fewer staff, we are training them on common skills sets so that less of us are able to handle more," said Walton. "We were worried about the UCS investment as it was so new but we are happy it. Sometimes you have to take a risk to get a reward."

Prior to purchase, though, he and his team visited Cisco labs to see how UCS integrated with the Nexus 1000v in the real world. Once implemented, the Cisco networking gear has worked well with the city's 200 miles of fiber.

"The virtual infrastructure has improved network service by about 300 to 400 percent," said Walton.

Greg Smith, senior architect for SunGard Enterprise Cloud Services, is another fan of the Cisco Nexus 1000v. Like San Francisco, he is using it in conjunction with VMware, a 10 GbE network and EMC to create a cloud. To support the cloud vision, Smith says you need to have virtual switches.

"You can't have separate stacks anymore or separate groups of personnel to support them," said Smith. "To take advantage of this new technology, you can't silo IT. This upgrade has enabled us to reorganize by function instead of technology. "

Emile Versoza, a senior network engineer at Sutter Health, also uses the Nexus 1000v. With over 2200 servers in production, he began by moving 300 x86 servers onto 12 ESX hosts holding 300 Virtual Machines (VMs). He also added the Nexus 1000V to provide virtualized networking.

He is now working at virtualizing the rest of his physical servers and also wants to make it possible to easily move workloads from the primary data center to the DR site which is 15 miles away. Virtualization will greatly simplify the process of moving workloads as they will already exist inside a VM.

The data center core uses Cisco Catalyst 6509s with another 6509 used for distribution. Access is handled by Nexus 1000Vs and Catalyst 4948s. Dual Cisco units exist at each layer for redundancy.

HP c7000 blade enclosures are also used within the data center with 16 HP BladeSystem blade servers per enclosure. Each blade has 6 NICs. Two deal with vMotion and other services while four are reserved for VMware data traffic.

"Prior to virtualization, network visibility was a big problem and troubleshooting was difficult," said Versoza. "The Nexus virtual switch resolved these issues. It provides a similar look and feel to a Cisco physical environment but has better port flexibility."